Shallow aeration of piggery waste treatment lagoons. II. Odour control

The effect of shallow aeration on odours from anaerobic lagoons treating piggery wastes was determined in the laboratory under conditions of approximately constant temperature (20°C). The loading rate to the simulated lagoon profiles was approximately 50 g BOD₅ m^?3 day^?1 and the average retention time was 128 days. The removal of organic pollutants and bacteria in this system has been discussed elsewhere.Shallow surface aeration to depths ranging from 8 to 40 cm reduced odours from piggery waste treatments. Chemical and organoleptic estimates consistently indicated that odour levels from all aerated treatments were similar and markedly better than those from the unaerated treatment.The average volatile sulphides levels in the aerated treatments were less than 5% of the levels found in the space above the unaerated treatment. The levels in the aerated treatments of less than 0.07 ppm were below the odour threshold limit of 0.1 ppm compared with 1.45 ppm in the unaerated column. Odour threshold dilution (OTD), and more particularly odour offensiveness, were also reduced by shallow surface aeration. The mean OTD values (log₁₀) of all lagoon treatments (unaerated 2.9 and <2.6 for aerated treatments) were less than that of the untreated waste (3.3) or from wastes stored anaerobically in underslat pits (4.2). Once perceived however, the offensiveness rating of odours from the unaerated treatment was greater (9.4) than from the aerated systems (<1.7).Volatile fatty acid (VFA) levels in the effluents from all treatments were negligible (< 0.01 g l^?1).Total VFA levels in the untreated waste were 2.1 g l^?1, of which approximately 57, 20 and 11% were acetic, propionic and n-butyric, respectively. Sludge VFA levels were about 0.2 g l^?1, of which 75% was acetic acid.     

水肥气耦合对温室番茄地土壤N2O排放及番茄产量的影响

为揭示水肥气耦合对温室番茄地土壤N_2O排放的影响,提出适宜的温室番茄增产减排措施,采用静态暗箱-气相色谱法监测土壤N_2O的排放,分析水肥气耦合条件下土壤温度、灌溉水利用效率(WFPS)、NO~-_3-N、O_2含量的变化规律以及N_2O排放的影响机制.加气条件下设两个灌水水平0.6 W和1.0 W(分别代表亏缺40%灌溉和充分灌溉,W代表充分灌水时的灌水量)和3个施氮水平(120、 180和240 kg·hm~(-2),分别代表低、中和高氮,以50%F、 75%F和F表示,其中F为当地推荐施氮量),以不加气充分灌溉(O为加气灌溉,CK为常规滴灌)条件下3种施肥水平为对照,共9个处理.结果表明,充分灌溉(W2F1O、W2F2O和W2F3O)的N_2O累积排放量较亏缺灌溉(W1F1O、W1F2O和W1F3O)处理平均增加了55.7%(P0.05);高氮条件下(W1F3O、W2F3O和W2F3CK)土壤N_2O排放较中氮和低氮平均增大13.4%和43.8%(P0.05),充分灌溉条件下加气处理(W2F1O、W2F2O和W2F3O)较相应不加气处理(W2F1CK、W2F2CK和W2F3CK)N_2O排放平均增加11.2%(P0.05).加气、施氮量和灌水量的增加可增加番茄产量和单产N_2O排放量.高氮处理番茄产量和单产N_2O排放量较中氮处理分别增加了12.5%(P0.05)和3.9%(P0.05),高氮处理番茄产量和单产N_2O排放量较低氮处理显著增加了30.4%和9.6%(P0.05),加气充分灌溉较加气亏缺灌溉处理番茄产量和单产N_2O排放量分别显著增加了29.7%和18.7%(P0.05),加气处理(W2F1O、W2F2O和W2F3O)较不加气处理产量(W2F1CK、W2F2CK和W2F3CK)平均增加了10.4%(P0.05),单产N_2O排放量增加但不显著.灌水量增加、施肥量降低、加气均可显著增大肥料偏生产力,减小灌溉水分利用效率(IWUE).综合考虑N_2O累积排放量、作物产量、氮肥利用效率、IWUE和单产N_2O排放量,得出加气低氮充分灌溉为较优的管理模式.本研究结果为温室番茄的增产减排提供了一定的参考.     

Effectiveness of short-term aeration in treating swine finishing manure to reduce odour generation potential

The work presented here is to elucidate removals of organic matter, nitrogen and odour generation potential in swine manure treated by short-term aeration. The experiment was composed of a 4 × 3 factorial design, with solids levels ranging from 0.5 to 4.0% and aeration lengths from 0.5 to 4.0 days at an airflow rate of 1.2 L s⁻¹ m⁻³. Manure samplings were conducted on days 5, 10, and 20 during the storage. Solids (TS: total solids; TVS: total volatile solids), 5-day biochemical oxygen demand (BOD₅), total Kjeldahl nitrogen (TKN), and volatile fatty acids (VFAs) for manure samples were measured to characterize the effectiveness of aeration. According to this study, solids (TS and TVS), BOD₅, TKN and VFAs were reduced in varying degrees with respect to the aeration length and storage time. Removal ratios of VFAs from 46.6 to 78.5, 49.4 to 86.9, and 48.8 to 95.6% were achieved under the aeration length of 0.5, 2.0, and 4.0 days, respectively. The variation of odour generation potential in the manure treated by short-term aeration can be linearly evaluated by the concentrations of solids, BOD₅, and/or TKN, but the feasibility could be impaired for manure with high solids content. Meanwhile, foaming was found troublesome during the process of short-term aeration. Four-day aeration is recommended to treat manure with a total solids level of less than 2.0% for odour control because over 70% of VFAs removal efficiencies can be achieved.     

Characterization of refuse landfill leachates of three di erent stages in landfill stabilization process

Landfill leachates with di erent ages (mature leachate, 11 years; semi-mature leachate, 5 years; fresh leachate, under operation) were collected from Laogang Refuse Landfill, Shanghai to characterize the colloid size distribution and variations of leachate. These leachates were separated using micro-filtration and ultra-filtration into specific size fractions, i.e., suspended particles (SP) (> 1.2 m), coarse colloids (CC) (1.2–0.45 m), fine colloids (FC) (0.45 m, 5 kDa/1 kDa molecular weight (MW)), and dissolved organic matters (DM, < 5 kDa/1 kDa MW). The specific colloids in each size fraction were quantified and characterized through chemical oxygen demands (COD), total solid (TS), pH, NH4 +-N, total organic carbon (TOC) and fixed solid (FS). It was found that COD, NH4 +-N and TS in leachate decreased significantly over ages, while pH increased. The dissolved fractions (< 5 kDa/1 kDa) dominated (over 50%) in three leachates in terms of COD, and the organic matter content in dissolved fraction of leachates decreased and the inorganic matter increased as the disposal time extended, with the TOC/COD ratio 30%–7%. Dissolved fractions decreased from 82% to 40% in terms of TOC as the disposal time extended, suggested that the organic matter remained in leachate would form into middle molecular weight substances during the degradation process.     

秸秆与化肥减量配施对菜地土壤温室气体排放的影响

采用静态箱/气相色谱法,2016年11月至2017年9月通过田间原位试验,设置了无物料还田(CK)、常规化肥(F)、秸秆还田配施100%化肥(100FS)、秸秆还田配施70%化肥(70FS)、秸秆还田配施60%化肥(60FS)、秸秆还田配施50%化肥(50FS),对比分析了在化肥减量的基础上,配施秸秆处理的菜地(莴笋-卷心菜-辣椒轮作)土壤CO_2、CH_4、N_2O动态变化特征及温室效应,研究秸秆与化肥减量配施对菜地温室气体排放的影响.结果表明,土壤CO_2、CH_4、N_2O排放具有一定的季节变化规律,排放高峰主要集中在4~8月,且在施肥灌水后均会出现气体的排放峰.秸秆与化肥配施较常规施肥(F)处理提高了土壤N_2O排放量,累积排放量及其排放系数,其中100FS处理的效果最为明显,辣椒季的累积排放通量明显高于莴笋季和卷心菜季,高达60.76 kg·hm~(-2)(P0.05),N_2O的排放系数(以N_2O-N/N计)为0.138 kg·kg-1,而秸秆与化肥减量配施较100FS处理可以降低氮肥的N_2O排放系数.与对照CK和F处理相比,70FS处理降低了土壤CO_2排放量和累积排放量,分别为55.28~1 831.62 mg·(m2·h)-1和7 502.13~25 988.55 kg·hm~(-2),而其他秸秆与化肥配施处理均增加了CO_2累积排放通量,尤其是60FS和50FS处理.对土壤CH_4排放而言,辣椒季的排放波动较大,除CK外,各处理的土壤CH_4累积排放量多为负值,表现为大气中CH_4汇;秸秆与化肥减量30%~50%配施处理均降低了辣椒季的土壤CH_4排放量和累积排放通量,而100FS处理提高了CH_4排放量和累积排放通量.与CK和F处理相比,除70FS外,100FS、60FS和50FS均显著提高了GWP.总体上,从温室气体排放角度,在常规化肥施用的基础上减量30%再与秸秆配施可以降低土壤CO_2和CH_4排放,缓解温室气体的增温潜势,而对土壤N_2O减排效果不显著.     

进水渗滤液总氮和BOD5/TN对填埋场反应器反硝化和厌氧氨氧化协同脱氮的影响

晚期垃圾渗滤液具有氨氮浓度较高、碳氮比(C/N)较低和可生化性差的特点,生物脱氮较困难.本文研究了改变进水总氮负荷和BOD5/TN比值对填埋场生物反应器处理垃圾渗滤液的脱氮效果的影响.结果表明,总氮负荷为15~25g·(m3·d)-1的范围内时,总氮去除负荷稳定为10~12 g·(m3·d)-1,但是总氮去除率随着负荷的增加从67.7%下降至60.2%,说明在一定范围总氮负荷的增加会降低总氮去除率,但不会影响去除负荷.当改变进水的BOD5/TN从0.3提高到0.4后,总氮负荷为9 g·(m3·d)-1时的厌氧、准好氧反应器,总氮去除率可从79.9%分别提高到89.9%和86.2%,表明提高BOD5/TN能够有效促进填埋场生物反应器对总氮污染物的去除,并且厌氧条件下效果更好.脱氮途径分析表明,填埋场生物反应器中厌氧氨氧化和反硝化作用可以协同脱氮.     

渗滤液回灌对其最终处理的影响中试研究

针对2座中试规模反应柱,分别考察渗滤液回灌和不回灌的情况,研究传统厌氧型生物反应器填埋场渗滤液回灌对其最终处理的影响.结果表明:回灌对渗滤液中的有机污染物有很好的去除效果,但对难降解物质以及氮、磷的净化效果不明显.回灌44周后,渗滤液的BOD5去除率达到98.5%,但出流的BOD₅/COD值仅为0.07,BOD₅/TN和BOD₅/TP分别为0.13和11,远低于厌氧条件下微生物生长适值,很难通过传统的生物处理方法净化.在设计生物反应器填埋场时,应该充分考虑到渗滤液经过回灌后组成特性,选择合适的渗滤液处理方案和填埋、回灌方式,充分利用垃圾体的净化作用.     

光合细菌接触氧化工艺的研究

一、前言 光合细菌法(简称PSB法)具有负荷高、效果好、占地省等优点,菌体污泥又有很高的营养价值,可以回收利用。因此这是近年来引人注目的一种废水资源化及综合利用的新技术。有不少排出高浓度有机废水的工厂,     

基于PCR-DGGE和拟杆菌(Bacteroides)16S rRNA的岩溶地下水粪便污染来源示踪研究:以重庆南山老龙洞地下河系统为例

岩溶地下水的微生物污染日益严重,其来源的研究得到国际学术界的广泛关注.本研究以重庆南山老龙洞岩溶地下河系统为对象,采用滤膜法监测地下水中的总细菌、大肠杆菌、粪大肠菌及粪链球菌等微生物指标,以拟杆菌(Bacteriodes)为指示细菌,采用PCR-DGGE示踪地下水中大肠杆菌/粪大肠杆菌的来源.结果表明,老龙洞地下河流域各类细菌含量严重超标,总细菌数为10~2.9×10~7CFU·m L~(-1),大肠菌群总数达4.3~4.0×10~5CFU·m L~(-1),其中粪大肠菌群(FC)和粪链球菌(FS)分别最高达到1.1×10~6CFU·(100 m L)~(-1)、1.1×10~5CFU·(100 m L)~(-1);FC/FS多数为2以上,暗示流域地下水受人类粪便影响为主.地下水样和粪便样品的拟杆菌群落的PCR-DGGE比对分析表明地下水与人粪之间相似性为7.1%~69.1%,其中地下河出口处达到69.1%.地下水与猪粪之间相似性为1.1%~53.4%,地下河出口处仅为1.5%.因此,人类粪便为地下河污染的主要来源,猪粪污染为动物粪便污染的一部分,还存在其他动物粪便污染来源.此外,PCR-DGGE产物切胶测序发现大部分Bacteroides为人类肠道或粪便来源的细菌.     

外循环气升式反应器中光合细菌处理味精废水的研究

外循环气升式反应器（ＥＡＬＲ）中球形红假单胞菌处理味精废水,能生产单细胞蛋白。在连续供气、ＫＬａ为２４２ｈ＾－１,ＨＲＴ为１２ｈ,活性炭载体浓度为１０ｇ／Ｌ,进水ＢＯＤ５为２７５０ｍｇ／Ｌ条件下,废水ＢＯＤ５的去除率达到９２％。载体增加反应器内生物量２８％,ＳＣＰ产率系数Ｙ＝０．５９ｋｇ（ｃｅｌｌ）／（ｋｇ ＢＯＤ５·ｄ）,是无载体组的２倍。ＥＡＬＲ的生物负荷为１．６８ｋｇ ＢＯＤ５／（ｋｇ ＭＬ     

有机肥与无机肥配施对潮土N2O排放的影响

华北平原是我国重要的粮食主产区,由于土壤有机质含量低,增加氮肥用量并不能导致玉米产量持续增加.有机肥和无机肥配施被广泛认为是同时实现粮食增产和提高土壤有机质的双赢措施,但是有机肥和无机肥配施对华北平原农田N_2O排放的影响尚不明确.本研究在华北平原潮土区,通过测定不同种类有机肥与无机肥配施后农田N_2O排放通量和作物产量,旨在揭示不同种类有机肥及其用量对潮土N_2O排放和作物产量的影响效应.田间试验共设置8个处理,分别为不施肥(CK)、化肥氮(NPK)、 40%牛粪氮+60%化肥氮(CM)、 40%鸡粪氮+60%化肥氮(FC)、 40%猪粪氮+60%化肥氮(FP)、 20%牛粪氮+80%化肥氮(1/2CM)、 20%鸡粪氮+80%化肥氮(1/2FC)和20%猪粪氮+80%化肥氮(1/2FP).整个玉米季N_2O排放通量均与土壤WFPS显著正相关(P0.05).除NPK处理外,玉米季N_2O排放量与土壤可溶性有机碳(DOC)平均含量存在显著的线性关系.玉米季CK处理N_2O排放量为0.50 kg·hm~(-2),NPK处理增加到2.28 kg·hm~(-2).相同用量不同种类有机肥处理,N_2O排放未出现显著差异. 40%有机肥氮用量处理下N_2O排放量与NPK处理无显著差异,而用量减少至20%后, 1/2CM、 1/2FC和1/2FP处理N_2O排放量分别较CM、 FC和FP减少了33.6%、 43.7%和12.1%,其主要原因为易分解有机碳输入减少,土壤DOC含量降低,但玉米产量未出现显著差异.因此,从减少温室效应的角度,玉米季80%化肥氮配施20%有机肥氮为本地区农田施肥的较佳选择.     

东北土著白腐真菌处理玉米秸秆纤维素乙醇废水的可行性探讨

青顶拟多孔菌是一种可以降解木质素的白腐真菌,也是具有较高的产漆酶能力的生产者.选择青顶拟多孔菌处理玉米秸秆纤维素乙醇废水,于液体培养青顶拟多孔菌中的锥形瓶中添加不同体积的废水,考察其对不同稀释比玉米秸秆纤维素乙醇废水的处理效果,并通过研究废水投加时间的调控,获得具有高木质素降解率且相对最短降解时间的工艺条件.结果表明:青顶拟多孔菌可从废水中去除50%以上的COD_Cr和23.8%的木质素.对不同稀释比例（1%~20%）玉米秸秆纤维素乙醇废水中木质素具有较好的去除效果,其中稀释6%废水的体系中降解木质素效果最好,在第10天木质素降解率达到73.5%.不同废水投加时间对青顶拟多孔菌处理稀释20%废水体系中木质素的降解效果影响较大,第5天投加废水可获得理想的木质素降解效果,在试验进行的第19天降解率达到68.4%;在投加废水时间不同的情况下,经青顶拟多孔菌处理后的各体系中BOD₅/COD_Cr均有所提升,并且都提升至0.58以上,其中第9天投加废水体系经处理后BOD₅/COD_Cr最大,达到0.64.研究结果可为青顶拟多孔菌处理玉米秸秆纤维素乙醇废水的实际应用提供参考.      

Growth and foliar injury responses of maize,soybean and tomato seedlings exposed to mixtures of ozone and sulphur dioxide

A full factorial experiment in controlled-environment chambers with three levels of ozone (O₃) (0, 0.08 and 0.15 μl l⁻¹) and four levels of sulphur dioxide (SO₂) (0, 0.03, 0.12 and 0.30 μl l⁻¹ for 6 h per day for 7 days) was used to obtain dose-response relationships for growth and foliar injury. Non-destructive covariate measurements were used to increase precision. All maize (Zea mays L., cv. Golden Jubilee) response variables had significant interactive effects between the pollutants. Soybean (Glycine max L., cv. Maple Arrow) leaf and stem dry weights had significant interactive effects between the pollutants. For tomato (Lycopersicon esculentum Mill., cv. New Yorker), leaf dry- and fresh-weights and visible injury had significant interactive effects between the pollutants. In all species, some growth variables were stimulated by the intermediate levels of single and/or combined pollutant treatments. In contrast, visible foliar injury increased with each concentration increment of single or mixed gases. A supplementary experiment involving two levels of O₃ and two levels of SO₂ indicated that dry matter allocation to roots and shoots varied with treatment and species.     

水分调控下旱地土壤中毒死蜱的消解研究

为探讨水分调控下旱地土壤中毒死蜱的消解特性,通过盆栽试验及通径分析方法,研究了不同水分条件下旱地土壤中毒死蜱消解速率及其与土壤性质之间的关系.结果表明:①土壤中毒死蜱的消解速率随时间的延长而逐渐减缓,并且不同水分条件下土壤中毒死蜱的消解速率不同,施药45 d后,5个水分处理（20% FC、40% FC、60% FC、80% FC和100% FC,表示田间持水量依次为20%、40%、60%、80%和100%）下毒死蜱的消解率分别为65.58%~85.56%、70.71%~89.64%、76.30%~95.33%、72.53%~97.60%和70.57%~90.80%,其中以80% FC下的消解速率最快,60% FC下次之.②一级动力学方程能较好地描述土壤中毒死蜱的消解过程（R2>0.88）,消解速率常数（k）最大为0.099 0 d-1.③土壤中毒死蜱的消解速率与w（有机碳）、w（DOC）（DOC为可溶性有机碳）和w（MBC）（MBC为微生物量碳）均呈显著相关.通径分析结果显示,水分条件的改变致使土壤中w（有机碳）、w（DOC）和w（MBC）发生变化,进而对土壤中毒死蜱的消解速率产生较大影响.④大豆、玉米和小麦根际土壤中毒死蜱消解速率均快于非根际土壤,根际土壤中毒死蜱消解速率表现为大豆土壤（0.099 0 d-1）>玉米土壤（0.080 6 d-1）>小麦土壤（0.069 6 d-1）.研究显示,改变土壤水分含量可有效调节土壤中毒死蜱的消解,并为农业生产中毒死蜱的安全施用提供参考依据.      

用高效染料脱色菌和PVA降解菌混合培养液处理印染废水

在厌气－好气－活性碳三级串联工艺系统中，用７株高效染料脱色降解菌在厌气池中接种，在好气池中用聚乙烯醇降解菌富集培养液接种挂膜处理含ＰＶＡ和ＢＯＤ５／ＣＯＤｃｒ＜０．２的印染废水，经日处理１７ｔ废水的中试表明，当进水ＣＯＤｃｒ，ＢＯＤ５，ＰＶＡ，洗涤剂和色度含量分别为６８０ｐｐｍ，１１０ｐｐｍ，１３４ｐｐｍ，２．９４ｐｐｍ和６５倍时，在厌气池，好气池和活性碳池中的水力负荷分别为３．１７，３．０，１４     

秸秆/生物炭施用对关中地区小麦-玉米轮作系统净增温潜势影响的对比分析

为探讨秸秆、生物质炭施用对小麦-玉米轮作系统固碳减排效应,利用静态暗箱-气相色谱原位监测小麦-玉米轮作系统条件下秸秆、生物质炭施用对土壤CO_2、CH4和N_2O 3种温室气体排放、作物产量、土壤有机碳以及净增温潜势的影响.试验处理设置为:空白对照(CK)、常规施肥(F)、施肥并施用8 t·hm-2秸秆(FS)、施肥并施用8 t·hm-2生物质炭(FBlow)和施肥并施用16 t·hm-2生物质炭(FBhigh)共5个处理.结果表明:与F处理相比,FS、FBlow及FBhigh处理下小麦产量分别提高了30.9%、66.3%和36.6%;对于玉米产量而言,FS,CK及FBhigh处理下玉米产量分别降低了14.1%、18.0%和24.6%,但是FBlow处理下对玉米产量没有显著性的影响.与F处理相比,FS处理下土壤CO_2的年排放总量增加了60.2%,但是FBhigh处理下土壤CO_2的年排放总量减低了14.4%;生物质炭的施用降低了土壤N_2O的排放,与F处理相比,FBlow和FBhigh处理下分别减低了27.6%和38.7%,而秸秆的施用对N_2O的排放没有显著性的影响.总的来说,与F处理相比,FBlow和FBhigh处理下净增温潜势分别降低了24.13和58.44 t·hm-2,单位产量的净综合增温潜势分别降低了1.78和5.06 t·t-1.综上所述,对于小麦-玉米轮作体系而言,施用16 t·hm-2生物质炭可作为一种提高作物产量并降低净增温潜势的良好措施.     

Petro-chemical wastewater treatment by biological process

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Nitrates leaching from agricultural land in Hamadan, western Iran

Nitrogen (N) is vital for plant and microbial growth and rather large amounts are required by most arable and horticulture plants. High nitrate (NO₃⁻) levels of water supplies have been attributed to leaching from the soil and into water systems. In the arid and semi-arid regions, irrigation water carries NO₃⁻ into groundwater. This study was conducted to investigate NO₃⁻ pollution of groundwater in Hamadan, western Iran. The water samples were mostly taken from domestic and community wells. In this area, the drinking water supply comes mainly from groundwater sources. Nitrate concentrations in the well samples varied from 3 to 252 with the average of 49 mg l⁻¹. Results showed that of 311 wells, 196 (63%) had levels less than 50 mg l⁻¹ and 115 (37%) had levels in excess of the 50 mg l⁻¹ NO₃⁻. Agriculture is the dominant land use in the area and application of N fertilizers clearly has an impact on groundwater. If agricultural losses remain stable, it could be expected that the concentration of NO₃⁻ in groundwater will reach or exceed the international recommendations for drinking water (50 mg l⁻¹) in the future. Irrigation with high NO₃⁻ groundwater can minimise the requirement for N fertilizers. To maintain yield increase and minimise NO₃⁻ pollution of the groundwater, best management practices, for N fertilizer use should be applied and excessive fertilizer application prevented.     

乙酰螺旋霉素废水生物处理的试验研究

采用相同体积 (6 2L)的升流厌氧污泥床和厌氧复合床处理乙酰螺旋霉素废水 ,当容积负荷为 6 0kg(COD) (m3 ·d)时 ,升流厌氧污泥床和厌氧复合床反应器对SS、COD、BOD5的去除率分别为 6 7 4 %、85 1%、91 2 %和 75 6 %、91 7%、96 1%,结果表明厌氧复合床是高效实用的厌氧生物反应器 ;厌氧出水采用相同体积 (6 4L)的生物接触氧化工艺和周期循环活性污泥系统进行处理 ,当容积负荷为 1 6kg(COD) (m3 ·d)时 ,生物接触氧化反应器和周期循环活性污泥系统对SS、COD、BOD5的去除率分别为 87 9%、85 1%、92 8%和 91 6 %、88 7%、95 4 %,结果表明周期循环活性污泥系统是高效实用的好氧生物反应器 .     

Coxsackievirus B4 as a Causative Agent of Diabetes Mellitus Type 1: Is There a Role of Inefficiently Treated Drinking Water and Sewage in Virus Spreading?

This study proposed to detect the enterovirus (EV) infection in children with type 1 diabetes mellitus (T1D) and to assess the role of insufficiently treated water and sewage as sources of viral spreading. Three hundred and eighty-two serum specimens of children with T1D, one hundred serum specimens of children who did not suffer from T1D as control, and forty-eight water and sewage samples were screened for EV RNA using nested RT-PCR. The number of genome copies and infectious units of EVs in raw and treated sewage and water samples were investigated using real-time (RT)-PCR and plaque assay, respectively. T1D markers [Fasting blood glucose (FBG), HbA1c, and C-peptide], in addition to anti-Coxsackie A & B viruses (CVs A & B) IgG, were measured in control, T1D-negative EV (T1D–EV^?), and T1D-positive EV (T1D–EV⁺) children specimens. The prevalence of EV genome was significantly higher in diabetic children (26.2%, 100 out of 382) than the control children (0%, 0 out of 100). FBG and HbA1c in T1D–EV^? and T1D–EV⁺ children specimens were significantly higher than those in the control group, while c-peptide in T1D–EV^? and T1D–EV⁺ children specimens was significantly lower than that in the control (n = 100; p < 0.001). Positivity of anti-CVs A & B IgG was 70.7, 6.7, and 22.9% in T1D–EV⁺, T1D–EV^?, and control children specimens, respectively. The prevalence of EV genome in drinking water and treated sewage samples was 25 and 33.3%, respectively. The prevalence of EV infectious units in drinking water and treated sewage samples was 8.5 and 25%, respectively. Quantification assays were performed to assess the capabilities of both wastewater treatment plants (WWTPs) and water treatment plants (WTPs) to remove EV. The reduction of EV genome in Zenin WWTP ranged from 2 to 4 log₁₀, while the reduction of EV infectious units ranged from 1 to 4 log₁₀. The reduction of EV genome in El-Giza WTP ranged from 1 to 3 log₁₀, while the reduction of EV infectious units ranged from 1 to 2 log₁₀. This capability of reduction did not prevent the appearance of infectious EV in treated sewage and drinking water. Plaque purification was performed for isolation of separate EV isolates from treated and untreated water and sewage samples. Characterization of the EV amplicons by RT-PCR followed by sequencing of these isolates revealed high homology (97%) with human coxsackievirus B4 (CV B4) in 60% of the isolates, while the rest of the isolates belonged to poliovirus type 1 and type 2 vaccine strains. On the other hand, characterization of the EV amplicons by RT-PCR followed by sequencing for T1D–EV⁺ children specimens indicated that all samples contained CV B4 with the same sequence characterized in the environmental samples. CV B4-contaminated drinking water or treated sewage may play a role as a causative agent of T1D in children.